The present invention refers to a device and method for reading a meter, particularly for reading a mechanical numerical totalizer meter provided with a plurality of decadic wheels for computing the progression of a physical quantity.
Domestic utilities, including gas, electricity and water, have always represented essential expenses in the management of a home or commercial business. Therefore, knowing the details as to consumption levels and having the possibility of monitoring them constantly is definitely essential for one's own self-interest and for saving some money on the final bill.
In the illustrative example of gas, the latter is metered by means of a meter that indicates the total volume of gas that has passed through a section of the pipe on which the meter is installed. These meters are universally employed on the premises of all combustible gas utility users, that is, residential, commercial, industrial users, etc.
There are different types of gas meters. As they are installed in homes, the meters most frequently used are diaphragm meters that are based on two measurement chambers (having a very precise volume) with deformable walls and that alternately fill up with gas and empty. Converted with a crank mechanism, this reciprocating movement, which is brought about by the difference in pressure between the inlet and outlet sections, is transmitted to a pinion that advances the decadic wheels of the mechanical totalizer located on the dial face. The sequence of numerical figures found on the decadic wheels will thus indicate the current gas consumption level.
As the meters are found in the respective homes or commercial businesses, the reading thereof must be carried out by a person (the actual user or personnel assigned to do this) who reads the sequence of figures on the decadic wheels on the dial face and then has to report it to the competent authority.
In recent years, also in response to requests by the competent authority for gas management, new types of meters (Smart Meters) have been installed, replacing the traditional mechanical totalizer with an electronic totalizer equipped with a device for data transmission. For the purposes of providing greater transparency concerning energy consumption, the Smart Meter or the household consumption digital meter detects and processes all important data, thus establishing a new criterion of efficiency in energy use and energy savings. Owing to this type of meter, a user can monitor consumption levels for their own home or commercial business and manage them more prudently. Moreover, by combining the meter with a data gateway, remote readings can be carried out. In this manner, the user and possibly the gas supplying agency can refer to current consumption data remotely at any time. The objective of the competent authority for gas is to reach the point of total replacement of the traditional mechanical totalizer meters with the more modern ones of the Smart Meter type. However, it will take several more years before the process of substituting the traditional meters can be completed.
For this reason, solutions are known that also enable remote reading for traditional meters that are provided with a mechanical totalizer.
For example, document DE 202008007959 U1 discloses a device for remote reading of a mechanical totalizer meter. This device utilizes optical sensors applied at the rotating disc or directly on the numerical display made up of the decadic wheels of the meter. In this latter case, the device has a camera and software for optical character recognition (OCR) so as to read the images on the numerical display and translate them into a data package that can be transferred in a wireless mode to a control center. However, although they can ensure satisfactory reading precision, systems of this type employ optical sensors such as CCD devices and optical recognition software that are very costly and bring about a considerable waste of energy.
Document EP0810548 A1 discloses a system for remote reading of a meter with a mechanical totalizer without using sophisticated software for recognition of the numerical figures. In this case, the meter is provided with a reference wheel associated with the movement of the decadic wheels of the totalizer. The reference wheel is covered with a highly absorbent material (black color) and partly with a highly reflective material (white color) and it is coupled to an infrared sensor and a LED light, the latter being an infrared LED light. Based on the different reflection of the light in different parts of the wheel, an associated electrical circuit will detect a different voltage for each rotation period. This information is then processed by a control system that can calculate the actual consumption of the meter. The reading system according to this document can also be implemented remotely. However, one disadvantage of this solution is that in order to operate, this system requires a reference wheel (or simply a marker), which is an element added to the traditional meter. Therefore, the system according to document EP0810548 A1 cannot be applied to any meter having a mechanical totalizer, since the latter must originally comprise a reference wheel or it must be modified by inserting suitable reference markers.